1. Field of the Invention
This invention relates to earthmoving apparatus and in particular to means for counterbalancing earthmoving apparatus, such as loaders and the like.
2. Description of the Prior Art
In one conventional form of backhoe apparatus marketed by the assignee hereof, a crawler-type drive machine is provided at one end with a backhoe mechanism. The backhoe is removably attached to the drive machine by a mounting group assembly. The assembly includes mounting brackets carried on the rear end of the drive machine. Hydraulic lines with quick disconnect couplers are provided for operating the backhoe from the drive machine. Conventionally, a counterweight is provided adapted to be mounted on the front end of the drive machine when the machine travels with the backhoe attached.
One example of earthmoving apparatus utilizing removable counterweights is shown in U.S. Letters Pat. No. 2,820,556 of George Davis. Therein, a counterweight is provided for a truck means, or similar industrial vehicle, which is selectively removably installed on a crane-supporting platform thereof.
In U.S. letters Pat. No. 2,967,718 of Herbert L. Orwig, a removable counterweight is provided on a vehicle, such as a fork truck or other material handling machine. The counterweight is provided with lugs engaging frame members on the machine and suspending the counterweight below the frame members. The counterweight may be removed from the vehicle by moving it longitudinally of the frame members.
Robert D. Straszheim et al, in U.S. Letters Pat. No. 3,003,785, show a weight-mounting means for use with tractors and the like utilizing a plurality of identical weights adapted to be used singly or in multiples, as desired. The weights are mounted by means of fasteners insertable from the front so that each added weight is carried by the weight preceding it.
In U.S. Letters Pat. No. 3,533,524, John H. Wilcox discloses a counterweight removal arrangement for hydraulic excavators or the like wherein a counterweight is swingably mounted at the rear of the working frame by means of vertical suspension members so that it can be lowered and dismounted by lifting the front end of the machine. In one embodiment, the suspension members are extensible and retractable to enable the counterweight to be lowered slightly before the front end of the machine is elevated.
In U.S. Letters Pat. No. 3,788,674 of Robert Casey, owned by the assignee hereof, a clamping mechanism for a side shiftable backhoe is provided whereby the backhoe is supported at an infinite number of positions transverse to the axis of the vehicle. The counterweight system of the present invention is well adapted for use with such a backhoe apparatus and is illustrated in connection with its use thereon. Thus, reference may be had to U.S. Letters Pat. No. 3,788,674 for a detailed understanding of the earthmoving apparatus arrangement and for this purpose, said patent is incorporated by reference herein.
In British Pat. No. 1,396,684 of Klockner-Humboldt-Deutz Aktiengesellschaft, a boom is provided on a tractor or similar vehicle for raising and lowering a ballast weight so that the weight may be mounted on or removed from the vehicle. The ballast weight comprises individual weights and a base part secured together by a rod-shaped securing means with a crossbar comprising a pivot bearing disposed on each side of the weights.